THURSDAY, Oct. 25 (HealthDay News) -- Learning a new language over a short period of time appears to make the brain grow, new research suggests.

The new study included young recruits at the Swedish Armed Forces Interpreter Academy who went from having no knowledge of a new language to speaking it fluently within 13 months. The recruits studied at a furious pace: from morning to evening, weekdays and weekends.

The recruits were compared to medicine and cognitive science students at a university (the "control" group), who also studied hard, but weren't learning a new language.

Both groups underwent MRI brain scans before and after a three-month period of intensive study. The scans showed that the brain structure of the control group remained unchanged, but certain parts of the brain of the language students grew.

This growth occurred in the hippocampus, a structure involved in learning new material and spatial navigation, and in three areas of the cerebral cortex.

Among the recruits, those who took naturally to learning a new language had greater growth in the hippocampus and areas of the cerebral cortex related to language learning, while those who had to put more effort into learning a new language had greater growth in an area of the motor region of the cerebral cortex, the investigators found.

"We were surprised that different parts of the brain developed to different degrees depending on how well the students performed and how much effort they had had to put in to keep up with the course," Johan Martensson, a researcher in psychology at Lund University in Sweden, said in a university news release.

Martensson noted that previous research has indicated that bilingual and multilingual people develop Alzheimer's disease at a later age.

"Even if we cannot compare three months of intensive language study with a lifetime of being bilingual, there is a lot to suggest that learning languages is a good way to keep the brain in shape," Martensson said.